What do I do? Take y' of the first equation and then set it equal to the slope of the second equation and solve for x? answer is A.

This is what I got:

Did I take the wrong route/ what would I do next?

You got the correct y1'. You're making the rest too complicated. If the tangent line of y1 is parallel to y2, they simply have the same slope. If you have the form y=mx+b, m is the slope. So the slope of y2 is -2. Set y1' = -2 and solve for the x values.